1. Field of the Invention
The present invention is directed to an improved design for solar-heated buildings. In particular, the present invention relates to improved designs for solar-heated buildings that offer improved ease of building design and construction, lower cost, and better performance over existing passive solar heating designs, particularly in climates with cloudy winters.
2. Discussion of Related Art
A number of known systems have been used to collect, hold and release solar energy. Existing solar collectors typically collect solar heat during one to ten days per month of sunny winter weather. These existing solar systems store the collected heat only on sunny days and release heat during cloudy weather. A large proportion of the world's population lives where winters are cloudy. Previously, solar architects have responded with a design strategy of collecting solar heat during the one to ten days per month of sunny winter weather, and then storing this heat and releasing it during cloudy weather. This design suffers from several disadvantages. For example, this design necessitates that a full size backup fossil fuel heater be used when heat storage gives out during the longest periods of cloudy weather. It requires a large thermal storage unit which is expensive and which can lose some of the heat it stores, and it requires a large solar collector area which faces the equator, the direction of the winter sun, and in addition is more expensive. The solar collector must occupy most of a south facing wall and/or roof, which places severe restrictions on the building's shape, orientation and appearance. The above restrictions make the design of a conventional solar heated building a highly skilled compromise between conflicting requirements of aesthetics, building shape, use and site limitations, cost, and solar efficiency. Solar space heating and daylighting have not yet fulfilled their promise because reconciliation of the conflicting requirements of solar efficiency, low cost, ease of construction, aesthetics, building shape and site is difficult and often impossible.
Various similar building designs for collecting and storing sunlight have been used in the past. Nevertheless, none of these known designs have provided an efficient means for incorporating the solar collector in a building without altering the aesthetics, shape, orientation or functionality of the structural design, or, alternatively, without sacrificing solar collection efficiency. The conventional solar heating systems require large thermal storage units, and large equator-facing solar collectors typically placed on south walls of buildings.
None of the previously known systems described above offers the important advantage of the ability to efficiently collect and store sunlight on cloudy days. Similarly, none of the above-described art locates solar collectors on the building's roof when the roof design is dictated by architectural rather than solar conditions; instead, solar collectors were located on the south walls or the roof of the building, thus requiring substantial modification of traditional building design and orientation.